Aneurysms occur in blood vessels in locations where, due to age, disease or genetic predisposition, insufficient blood vessel strength or resiliency may cause the blood vessel wall to weaken and/or lose its shape as blood flows it, resulting in a ballooning or stretching of the blood vessel at the limited strength/resiliency location, thus forming an aneurysmal sac. Left untreated, the blood vessel wall may continue to expand to the point where the remaining strength of the blood vessel wall cannot hold and the blood vessel will fail at the aneurysm location, often with fatal result.
Various implantable medical devices and minimally invasive methods for implantation of these devices have been developed to deliver these medical devices with the lumen of a body vessel. These devices are advantageously inserted intravascularly, for example, from an implantation catheter. For example, to prevent rupture of an aneurysm, a stent graft of a tubular construction may be introduced into the blood vessel and deployed and secured in a location within the blood vessel such that the stent graft spans the aneurysmal sac. The outer surface of the stent graft, at its opposed ends, abuts and seals against the interior wall of the blood vessel at a location where the blood vessel wall has not suffered a loss of strength or resiliency. The stent graft channels the blood flow through the hollow interior of the stent graft, thereby reducing, if not eliminating, any stress on the blood vessel wall at the aneurysmal sac location.
Bifurcated medical devices may be implanted for the repair of an aneurysm at or in the vicinity of the aortic bifurcation. Typically, a bifurcated device comprises a main body and two tubular legs joining the main body in a bifurcation. In many instances, both the main body and each of the legs are stented. Due to this design, intravascular implantation may be complicated because the bifurcated device may have a relatively large delivery profile. A large delivery profile makes treating patients with tortuous anatomy or those having smaller arteries very difficult and, in some cases, impossible. A decrease in the delivery profile of a bifurcated device provides possibilities of treatment for these patients they made not have had. Additionally, a smaller more flexible device may reduce the incidence of iliac artery ruptures or damage.